package com.gict.antifraudback.utils;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;
import java.security.Key;
import java.security.spec.AlgorithmParameterSpec;
import java.util.Locale;

/**
 * 加密
 */
public class DESCode {
    private static final String key="povckmb84.'!@#!@a13513asssdsgdda770a";
    public static final String ALGORITHM_DES = "DES/CBC/PKCS5Padding";
    public static String encode(String data) {
        if (data == null){
            return null;
        }
        try {
            DESKeySpec dks = new DESKeySpec(key.getBytes());
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            Key secretKey = keyFactory.generateSecret(dks);
            Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
            IvParameterSpec iv = new IvParameterSpec("12345678".getBytes());
            AlgorithmParameterSpec paramSpec = iv;
            cipher.init(Cipher.ENCRYPT_MODE, secretKey, paramSpec);
            byte[] bytes = cipher.doFinal(data.getBytes());
            return byte2String(bytes);
        } catch (Exception e) {
            e.printStackTrace();
            return data;
        }
    }

    public static void main(String[] args) {
//        System.out.println(encode("123456"));
        System.out.println(decode("A9AA1F7F1F65BCC0"));
   }

    public static String decode( String data) {
        if (data == null){
            return null;
        }
        try {
            DESKeySpec dks = new DESKeySpec(key.getBytes());
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            Key secretKey = keyFactory.generateSecret(dks);
            Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
            IvParameterSpec iv = new IvParameterSpec("12345678".getBytes());
            AlgorithmParameterSpec paramSpec = iv;
            cipher.init(Cipher.DECRYPT_MODE, secretKey, paramSpec);
            return new String(cipher.doFinal(byte2hex(data.getBytes())));
        } catch (Exception e) {
            e.printStackTrace();
            return data;
        }

    }
    private static String byte2String(byte[] b) {
        StringBuilder hs = new StringBuilder();
        String stmp;
        for (int n =0;b != null && n < b.length; n++) {
            stmp = Integer.toHexString(b[n] & 0XFF);
            if (stmp.length() == 1){
                hs.append('0');
            }
            hs.append(stmp);
        }
        return hs.toString().toUpperCase(Locale.CHINA);

    }
    private static byte[] byte2hex(byte[] b) {
        if ((b.length% 2) != 0){
            throw new IllegalArgumentException();
        }
        byte[]b2 = new byte[b.length / 2];
        for (int n = 0;n < b.length; n += 2)
        {
            String item = new String(b, n, 2);
            b2[n / 2] = (byte)Integer.parseInt(item, 16);
        }
        return b2;
    }
}